ICU4C test case TestShortZoneIDs started failing since the beginning of this year.
FAIL: Time Zone PLT use daylight is FALSE but it should be TRUE
---ERRORS (1) in TestShortZoneIDs
The test case calls useDaylightTime and check if the returned value matches the hardcoded test data. "PLT" is an alias of "Asia/Karachi" defined by ICU for JDK compatibility support. The zone used daylight saving time in year 2008 (tzdata 2008c). But as of now, no plan for 2009. useDaylightTime checks if DST is observed in the current calendar year. Thus, it used to return true until Jan 1, 2009. We could simply change the test data to false to get rid of this problem. However, it looks such test case introduce confusions to ICU users who maintain tzdata (and run the test for verification). We should find out a better solution to make test case more stable.
For ICU4J, the test data for "PLT" was commented out because ICU4J used to rely on JDK TimeZone data and the implementation for "PLT" was not stable. There is no good reason to skip the test data now, because ICU4J has its own data.
